<?php
/**
 * PHPMailer - PHP email creation and transport class.
 * PHP Version 5.4
 *
 * @package PHPMailer
 * @link https://github.com/PHPMailer/PHPMailer/ The PHPMailer GitHub project
 * @author Marcus Bointon (Synchro/coolbru) <phpmailer@synchromedia.co.uk>
 * @author Jim Jagielski (jimjag) <jimjag@gmail.com>
 * @author Andy Prevost (codeworxtech) <codeworxtech@users.sourceforge.net>
 * @author Brent R. Matzelle (original founder)
 * copyright 2012 - 2014 Marcus Bointon
 * copyright 2010 - 2012 Jim Jagielski
 * copyright 2004 - 2009 Andy Prevost
 * license http://www.gnu.org/copyleft/lesser.html GNU Lesser General Public License
 * @note This program is distributed in the hope that it will be useful - WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.
 */

/**
 * PHPMailerOAuth - PHPMailer subclass adding OAuth support.
 *
 * @package PHPMailer
 * @author @sherryl4george
 * @author Marcus Bointon (@Synchro) <phpmailer@synchromedia.co.uk>
 */
class PHPMailerOAuth extends PHPMailer {
	/**
	 * The OAuth user's email address
	 *
	 * @var string
	 */
	public $oauthUserEmail = '';

	/**
	 * The OAuth refresh token
	 *
	 * @var string
	 */
	public $oauthRefreshToken = '';

	/**
	 * The OAuth client ID
	 *
	 * @var string
	 */
	public $oauthClientId = '';

	/**
	 * The OAuth client secret
	 *
	 * @var string
	 */
	public $oauthClientSecret = '';

	/**
	 * An instance of the PHPMailerOAuthGoogle class.
	 *
	 * @var PHPMailerOAuthGoogle
	 */
	protected $oauth = null;

	/**
	 * Get a PHPMailerOAuthGoogle instance to use.
	 *
	 * @return PHPMailerOAuthGoogle
	 */
	public function getOAUTHInstance() {
		if (!is_object($this->oauth)) {
			$this->oauth = new PHPMailerOAuthGoogle(
				$this->oauthUserEmail,
				$this->oauthClientSecret,
				$this->oauthClientId,
				$this->oauthRefreshToken
			);
		}
		return $this->oauth;
	}

	/**
	 * Initiate a connection to an SMTP server.
	 * Overrides the original smtpConnect method to add support for OAuth.
	 *
	 * @param array $options An array of options compatible with stream_context_create()
	 * @uses SMTP
	 * @return bool
	 * @throws PhpmailerException
	 */
	public function smtpConnect( $options = array() ) {
		if (is_null($this->smtp)) {
			$this->smtp = $this->getSMTPInstance();
		}

		if (is_null($this->oauth)) {
			$this->oauth = $this->getOAUTHInstance();
		}

		// Already connected?
		if ($this->smtp->connected()) {
			return true;
		}

		$this->smtp->setTimeout($this->Timeout);
		$this->smtp->setDebugLevel($this->SMTPDebug);
		$this->smtp->setDebugOutput($this->Debugoutput);
		$this->smtp->setVerp($this->do_verp);
		$hosts = explode(';', $this->Host);
		$lastexception = null;

		foreach ($hosts as $hostentry) {
			$hostinfo = array();
			if (!preg_match('/^((ssl|tls):\/\/)*([a-zA-Z0-9\.-]*):?([0-9]*)$/', trim($hostentry), $hostinfo)) {
				// Not a valid host entry
				continue;
			}
			// $hostinfo[2]: optional ssl or tls prefix
			// $hostinfo[3]: the hostname
			// $hostinfo[4]: optional port number
			// The host string prefix can temporarily override the current setting for SMTPSecure
			// If it's not specified, the default value is used
			$prefix = '';
			$secure = $this->SMTPSecure;
			$tls = ( 'tls' == $this->SMTPSecure );
			if ( 'ssl' == $hostinfo[2] || ( '' == $hostinfo[2] && 'ssl' == $this->SMTPSecure ) ) {
				$prefix = 'ssl://';
				$tls = false; // Can't have SSL and TLS at the same time
				$secure = 'ssl';
			} elseif ('tls' == $hostinfo[2]) {
				$tls = true;
				// tls doesn't use a prefix
				$secure = 'tls';
			}
			//Do we need the OpenSSL extension?
			$sslext = defined('OPENSSL_ALGO_SHA1');
			if ('tls' === $secure || 'ssl' === $secure) {
				//Check for an OpenSSL constant rather than using extension_loaded, which is sometimes disabled
				if (!$sslext) {
					throw new PhpmailerException($this->lang('extension_missing') . 'openssl', self::STOP_CRITICAL);
				}
			}
			$host = $hostinfo[3];
			$port = $this->Port;
			$tport = (int) $hostinfo[4];
			if ($tport > 0 && $tport < 65536) {
				$port = $tport;
			}
			if ($this->smtp->connect($prefix . $host, $port, $this->Timeout, $options)) {
				try {
					if ($this->Helo) {
						$hello = $this->Helo;
					} else {
						$hello = $this->serverHostname();
					}
					$this->smtp->hello($hello);
					//Automatically enable TLS encryption if:
					// * it's not disabled
					// * we have openssl extension
					// * we are not already using SSL
					// * the server offers STARTTLS
					if ($this->SMTPAutoTLS && $sslext && 'ssl' != $secure && $this->smtp->getServerExt('STARTTLS')) {
						$tls = true;
					}
					if ($tls) {
						if (!$this->smtp->startTLS()) {
							throw new PhpmailerException($this->lang('connect_host'));
						}
						// We must resend HELO after tls negotiation
						$this->smtp->hello($hello);
					}
					if ($this->SMTPAuth) {
						if (!$this->smtp->authenticate(
							$this->Username,
							$this->Password,
							$this->AuthType,
							$this->Realm,
							$this->Workstation,
							$this->oauth
						)
						) {
							throw new PhpmailerException($this->lang('authenticate'));
						}
					}
					return true;
				} catch (PhpmailerException $exc) {
					$lastexception = $exc;
					$this->edebug($exc->getMessage());
					// We must have connected, but then failed TLS or Auth, so close connection nicely
					$this->smtp->quit();
				}
			}
		}
		// If we get here, all connection attempts have failed, so close connection hard
		$this->smtp->close();
		// As we've caught all exceptions, just report whatever the last one was
		if ($this->exceptions && !is_null($lastexception)) {
			throw $lastexception;
		}
		return false;
	}
}
